Renewable fuse



June 10, 1924. 1,497,322

' H. E. BUTLER RENEWABLE FUS 8 Filed Sept. 17. 1921 v Inventor:

ijemy Efiuuer,

Hi5 Attorne Patented June 10, 1924.

UNITED STATES 1,497,322 PATENT OFFICE.

HENRY E. BUTLER, OF SCI-IENECTADY, NEW YORK, ASSIGNOR- TO GENERAL ELECTRIC COMPANY, 15. CORPORATION OF NEE-$1 YORK.

RENENABLE FUSE.

Application filed September 17, 1921.

T all whom it may concern:

Be it known that I, HENRY E. BUTLER,

a citizen of the United States, residing at Schenectady, county of Schenectady, State of New York, have invented certain new and useful Improvements in Renewable Fuses, of which the following is a specification.

The present invention relates to fuses such as are used to protect electrical inachinery and has for its object to provide an improved structure and arrangement in a fuse whereby the same can be readily renewed whenever it is burned out. A further object of my invention is to provide an arrangement whereby it is insured that when a fuse is renewed, it will be renewed with fuse material similar to that burned out so there will be no danger of renewing the fuse with fuse wire of too great or too little current-carrying capacity.

For a consideration of what I believe to be novel and my invention, attention is directed to the accompanying description and the claim appended thereto.

My invention is well adapted for use in. connection with fuses used to protect the windings of transformers and I have specifically illustrated and described it as applied to this use. It will be understood, however, that it is not necessarily limited thereto.

In the drawing, Fig. 1 is a sectional view of a transformer fuse embodying my inven tion; Fig. 2 is a sectional view taken at a right angle to Fig. 1; Fig. 3 is a perspective view of a magazine fuse; Fig. 4 is a perspectiye view of a modified form of magazine fuse; and Fig. 5 is a perspective View of contacts of a fuse showing the magazine fuse of Fig. 3 connected thereto.

Referring to the drawing, indicates a housing made of suitable insulating ma terial, such as porcelain, and provided with openings 11 to receive screws or bolts for fastening it to a support. In housing 10 is a ledge 12 on which are fixed two line contacts A and B- alike in structure and arranged diagonally opposite each other. As shown in perspective in Fig. 5, each contact comprises a base 13 which lies against ledge 12 and is fastened thereto by a suitable screw 14 extending through hole 14. On base 13 is a head 15 provided with a passa e 16 which stands in line with a hole 17 in. casing 10 and which is adapted to re- Serial No. 501,304.

ceive the end of an electrical conductor wire. In head 15 are set screws 18 for fastening a conductor end in passage 16. Base 13 is provided with an angular extension 19 under which lies the central portion of a U-shaped spring contact 20 which is fastened thereto by a screw 21. The ends of contact 20 are bent inwardly on themselves to provide a pair of spaced spring fingers 22 adapted to receive a contact blade between them. Adjacent one edge of contact 20 is a spring-locking plate 23 having a vertically extending slot 24, at the lower edge of which is a struck-out lip 25. Plate 23 is fixed in position by an angular extension 26 which is fastened under the head of screw 14.

The fuse and contact blades for connecting together contacts A and B are carried by a member made of insulating material and comprising a head 30 provided on one side with a knob 31 and on the other side with a long nose 32 having longitudinally extending ribs 33 on its sides which form a groove extending up one side of the nose, across its top and down the other side.

Nose 32 is adapted to enter housing 10 and the groove on it is adapted to receive a fuse wire or ribbon. At the base of nose 32 on opposite sides of it are fixed two contact blades and 36 adapted to engage spring contacts 20. Blades 35 and 36 are fastened in position by integral angular extensions 37 and 38 which lie against the sides of nose 32 and are held by screws 37 and 38*. In the ends of extensions 37 and 38 are binding screws 39 and 40. Contact blades 35 and 36 are each provided with beveled edges 41 which terminate in curved shoulders 42 and when the blades are moved into engagement with contacts 20 the beveled edges 41 ride along the ends of spring-locking plates 23 putting them under tension so that when shoulders 42 reach slots 24 the spring plates will snap over the shoulders as shown at the right-hand side of Fig. 1 thus locking the contact blades in engagement with the spring contacts. It will be clear that when contact blades 35 and 36 are connected by afuse wire and are brought into engagement with line contacts A and B a circuit will be closed through the fuse.

My invention relates particularly to the fuse arrangement and in carryingit out I provide a suitable casing or magazine 45 in which is a roll of fuse material 46 of sufi= cient length to forma number of fuses.

Fuse material 46 may be fiat, i. e., in the form of ribbons, as shown in Fig. 3, or it may be round as shown in Fig. 4. Magazine is made of suitable metal and is located below contact screw 39 and preferably directly adjacent head 30. It is fixed in place by an integral extension 47 which extends across extension 37 and is provided with a hole 48 through which screw 39 passes. Under the head of screw 39 and on top extension 47 is a clamping plate 49 be tween which and extension'47 a fuse ribbon or wire may be clamped by screw 39 and un- V fuse casing with a roll of fuse material contact blade 35.

therein in place with extension 47 lying over extension 37 and replace screw 39. Suflicient fuse wire'or ribbon is nowunwo-und from the roll by pulling on the end ofit to reach over the endof nose 32 and down to The free end of the fuse material is now fastened between clamping plate50 and extension 38 by loosening bindingscrew 40, slipping the end of the fuse material between the plate and extension and tightening again the screw. The fuse material adjacent casing 45 is fastened be tween extension 47 and clamping'plate 49 by slipping it between the two and tightening binding screw 39. If now the fuse blows, it is only necessary to remove head 30 from casing 10, loosen screws 39 and 40, pull out a new length of fuse material from the roll, fasten it to the contact blades by tightening again screws 39 and 40, and replace the head again. This is a. simple operation, easily and quickly performed and requires the use of only a screw driver. The roll may contain sufficient fus material for a number of renewals and when entirely 1 used, a new the roll of fuse, material so there is no danger of its becoming fusedl And it is takes place at the end of nose 32. But in eny-event,'the fuse magazine is sufliciently far from clamping plate 49 to insure that enced in actual use with fuses of this general character has been that an. attendant was likely to replace a blown fuse with any fuse material he might have at hand irrespective of its carrying capacity; or failing to have a piece of fuse material handy, he

would put in a piece of ordinary wire. As a result electrical apparatus has often been burned out because of the use of improper fuse material.

present a supply of fuse material of proper carrying capacity and the simplestand easiest thing is to renew the fuse with it.

My invention may be read'ly adapted and applied to existing structures with but slight changes if any, no change whatever in existing structures being required in the particular case illustrated.

In accordance with the provisions of the patent statutes, I have described the princi ples of operation of my invention, together with the apparatus which I now consider to represent the best embodiment thereof; but I desire to have it understood that the apparatus shown is only illustrative, and that the invention may be carried out by other means. i 7

hat I claim as new and desire to secure by Letters Patent of the United States, is,

In combination, a housing open at one end and closed at the other end to form a socket, contacts at the mouth of the socket, a fuse carrying member comprising a head and a nose, 'contacts fixed to the fuse-carrying member adjacent to its head for engagement with the socket contacts, binding posts carried by said contacts, a. closed receptacle having a supply offuse'materi al therein, said receptacle being provided with a'slot through whichthe end of the fuse material extends, and means fastening said receptacle to the fuse-carrying member adjacent to'o-ne of the contacts thereon and outside it as regards th fiow of current whereby fuse ma terial from said receptacle may be supplied for fastening to such contact and extending therefrom over said nose to the other con tact on the fuse-carrying member, thejfuse material in the receptacle being outside the electric circuit when the fuse-carrying meniber. isinserted into the socket to bring its contacts into engagement Wlththe housing contacts. I i p In witness whereof, I have hereunto set my hand this 16th day of se pteinbei3l9z2li HENRY E. BUTLER.

lVith my invention this difculty 1s obviated because there 1s always 

